I. Field
The present disclosure relates generally to wireless communications, and more specifically to techniques for recovering from a resource mismatch in a wireless communication system.
II. Background
Wireless communication has penetrated nearly every aspect of an individual's daily routine. To facilitate work/school activities as well as entertainment, wireless systems are widely deployed and provide various types of communication content such as voice, data, video, and so on. These systems can be multiple-access systems that are capable of supporting communication for multiple terminals by sharing available system resources. Examples of such multiple-access systems include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, and Orthogonal Frequency Division Multiple Access (OFDMA) systems.
A wireless multiple-access communication system can simultaneously support communication for multiple wireless terminals. In such a system, each terminal can communicate with one or more sectors via transmissions on the forward and reverse links. The forward link (or downlink) refers to the communication link from the sectors to the terminals, and the reverse link (or uplink) refers to the communication link from the terminals to the sectors. These communication links can be established via a single-input-single-output (SISO), multiple-input-single-output (MISO), and/or multiple-input-multiple-output (MIMO) systems.
Multiple terminals can simultaneously transmit on the reverse link by multiplexing their transmissions to be orthogonal to one another in the time, frequency, and/or code domain. If full orthogonality between transmissions is achieved, transmissions from each terminal will not interfere with transmissions from other terminals at a receiving sector. However, complete orthogonality among transmissions from different terminals is often not realized due to channel conditions, receiver imperfections, and other factors. As a result, terminals often cause some amount of interference to other terminals communicating with the same sector. Furthermore, because transmissions from terminals communicating with different sectors are typically not orthogonal to one another, each terminal can also cause interference to terminals communicating with nearby sectors. This interference results in a decrease in performance at each terminal in the system, with the ensuing deterioration of quality of service (QoS). In order to preserve QoS, communication need to reconcile interference levels with resources assigned for communication. Accordingly, there is a need in the art for effective techniques to mitigate the effects of interference and assign resources compatible with operational interference levels in a wireless communication system.